Tootfinder

Why the future belongs to "stellar" societies.
https://bigthink.com/the-long-game/the-tony-seba-and-james-arbib-interview-why-the-future-belongs-to-stellar-societies/

The Tony Seba and James Arbib interview: Why the future belongs to "stellar societies”
The cofounders of think tank RethinkX are convinced that humanity is undergoing civilizational phase change.

Secular Attrition of Classical Bulges by Stellar Bars
Rachel Lee McClure, Tobias G\'eron, Elena D'Onghia, Angus Beane, Aaryan Thusoo, Kathryne J. Daniel, Carrie Filion, Scott Lucchini
https://arxiv.org/abs/2506.09150

Secular Attrition of Classical Bulges by Stellar Bars
Classical bulges and stellar bars are common features in disk galaxies and serve as key tracers of galactic evolution. Angular momentum exchange at bar resonances drives secular morphological changes throughout the disk, including bar slowing and lengthening, and affects the structure of accompanying bulges. In this study, using a suite of N-body simulations, we quantify the secular reconfiguration of classical bulges through resonant trapping by evolving stellar bars. We use orbital frequency …

Probing Non-Thermal Processes in Stellar Flares on AU Mic
Adalyn Gibson, Adam F. Kowalski, Adina D. Feinstein
https://arxiv.org/abs/2506.10201 https://

Probing Non-Thermal Processes in Stellar Flares on AU Mic
The role of non-thermal proton energy transportation during solar and stellar flares is largely unknown; a better understanding of this physical process will allow us to rectify longstanding deficiencies in flare models. One way to detect the presence of non-thermal protons during flares is through the Orrall-Zirker (OZ) effect whereby an enhanced red wing appears in hydrogen emission lines (e.g., Lyman-$α$ at 1215.67 Angstrom). We analyze archival Hubble Space Telescope/Cosmic Origins Spectro…

QPEs from EMRI Debris Streams Impacting Accretion Disks in Galactic Nuclei
Itai Linial, Brian D. Metzger, Eliot Quataert
https://arxiv.org/abs/2506.10096 h…

QPEs from EMRI Debris Streams Impacting Accretion Disks in Galactic Nuclei
Quasi-periodic eruption (QPE) sources in galactic nuclei are often associated with a stellar object orbiting a supermassive black hole with hours-days period, brought in as an extreme mass-ratio inspiral (EMRI). In the presence of an accretion disk, repeated star-disk collisions lead to ablation of a small fraction of the stellar mass during each disk passage. We analytically follow the evolution of the stellar debris as it is tidally stretched outside the EMRI's Hill sphere, forming an elongat…

Constraints on Quaoar's rings and atmosphere from JWST/NIRCam observations of a stellar occultation
Benjamin Proudfoot, Bryan Holler, Ko Arimatsu, Flavia Rommel, Cameron Collyer, Estela Fern\'andez-Valenzuela
https://arxiv.org/abs/2506.07898

Constraints on Quaoar's rings and atmosphere from JWST/NIRCam observations of a stellar occultation
Observations of stellar occultations have revealed that small bodies are capable of hosting ring systems. The trans-Neptunian object (TNO) Quaoar, is the host of an enigmatic ring system, with two rings located well-outside the Roche limit. To better understand these structures, we observed a stellar occultation by Quaoar and its rings using the James Webb Space Telescope's (JWST) NIRCam instrument. Our observations detect both known rings, although Q2R -- the inner known ring -- is not detecte…

The presentations at the 2nd #AAS246 presser were about the papers https://iopscience.iop.org/article/10.3847/2041-8213/adc911 (Discovery of the Seven-ring Polycyclic Aromatic Hydrocarbon Cyanocoronene (C24H11CN) in GOTHAM Observations of TMC-1, also https://public.nrao.edu/news/cosmic-chemistry-breakthrough-largest-aromatic-molecule-found-in-deep-space/), https://arxiv.org/abs/2506.05575 (A map of the outer gas disk of the Galaxy with direct distances from young stars, also https://www.uah.edu/news/items/uah-researcher-unveils-new-map-of-milky-way-galaxy-in-atomic-hydrogen-revealing-its-clumped-flocculent-nature-for-first-time) and https://iopscience.iop.org/article/10.3847/1538-4357/adbbd9 (Surveying the Giant H ii Regions of the Milky Way with SOFIA. VII. Galactic Center Regions Sgr B1, Sgr B2, and Sgr C, also https://www.seti.org/press-release/unusual-stellar-nurseries-near-our-galaxys-center-puzzle-scientists) plus two results with apparently neither papers nor press releases going with them.

Implications of Rastall Theory on Stellar Solutions admitting Vanishing Complexity: A New Perspective
Tayyab Naseer
https://arxiv.org/abs/2507.07425 https:…

Implications of Rastall Theory on Stellar Solutions admitting Vanishing Complexity: A New Perspective
In this paper, the notion of complexity factor and its implication is extended to the framework of non-conserved Rastall theory of gravity. First of all, the field equations governing a static spherical geometry associated with the anisotropic fluid are formulated. The mass function corresponding to the considered geometry is defined in terms of both matter and geometric quantities. The orthogonal decomposition of the Riemann tensor is then performed through which a family of scalar quantities,…

ABYSS III: Observing accretion activity in young stars through empirical veiling measurements
Serat Saad, Marina Kounkel, Keivan G. Stassun, A. Roman-Lopes, Carlos G. Rom\'an-Z\'u\~niga, Jinyoung Serena Kim, Jonathan C. Tan, R. Lopez-Valdivia
https://arxiv.org/abs/2506.09826

ABYSS III: Observing accretion activity in young stars through empirical veiling measurements
Stellar accretion plays an important role in the early stages of stellar evolution, particularly in Classical T Tauri Stars (CTTSs). Accretion of a CTTS can be related to different physical parameters such as effective temperature (T$_{\text{eff}}$), age, abundance of hydrogen, etc. We can infer how accretion works by examining it across different wavelength regions. Accretion can be traced using veiling, a parameter that measures how excess emission from accretion affects the photospheric spec…

The Primakoff effect: axion-photon mixing in the context of axion electrodynamics
Bernard Teles de Menezes
https://arxiv.org/abs/2506.09103 https://…

The Primakoff effect: axion-photon mixing in the context of axion electrodynamics
We propose in this work the study of the production of axions in stellar plasma medium through an external magnetic field. In the background field approximation, we can show that the presence of the external magnetic field induces a mixing between the photon and the axion, i.e. the so called Primakoff effect. Since the axion is one of the greatest candidates for dark matter, for being a neutral pseudo-scalar field, the Primakoff process constitutes a mechanism (or portal) to access the dark sec…

Stellar Ancestry Unlocked: Chemical and Orbital Clues Link Metal Poor Stars to Globular Clusters and the Galaxy's Thick Disk
Gizay Yolalan, Timur \c{S}ahin, Sel\c{c}uk Bilir, Olcay Plevne
https://arxiv.org/abs/2506.10400

Stellar Ancestry Unlocked: Chemical and Orbital Clues Link Metal Poor Stars to Globular Clusters and the Galaxy's Thick Disk
This study presents a detailed chemical, kinematic, and orbital dynamic analysis of five metal poor stars in the solar neighborhood: HD 2665, HD 5916, HD 122956, HD 189349, and HD 218857. Using high-resolution spectroscopic data from the ELODIE and ESPaDOnS instruments, we derived elemental abundances for 29 species (25 elements: C, O, Na, Mg, Al, Si, S, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Y, Zr, Ba, Ce, Nd, and Sm) via LTE based analysis with ATLAS9 model atmospheres. Notably, we re…

Performance of MAGIC stellar intensity interferometer and expansion to MAGIC CTAO-LST1 stellar intensity interferometer
Alejo Cifuentes, V. A. Acciari, F. Barnes, G. Chon, E. Colombo, J. Cortina, C. Delgado, C. D\'iaz, M. Fiori, D. Fink, T. Hassan, I. Jim\'enez Mart\'inez, I. Jorge, D. Kerszberg, E. Lyard, G. Mart\'inez, R. Mirzoyan, M. Polo, N. Produit, J. J. Rodr\'iguez-V\'azquez, P. Saha, T. Schweizer, D. Strom, R. Walter, C. W. Wunderlich, MAGIC Collaborat…

Performance of MAGIC stellar intensity interferometer and expansion to MAGIC + CTAO-LST1 stellar intensity interferometer
A new generation of optical intensity interferometers are emerging in recent years taking advantage of the existing infrastructure of Imaging Atmospheric Cherenkov Telescopes (IACTs). The MAGIC SII (Stellar Intensity Interferometer) in La Palma, Spain, has been operating since its first successful measurements in 2019 and its current design allows it to operate regularly. The current setup is ready to follow up on bright optical transients, as changing from regular gamma-ray observations to SII…

Why Do Stars Turn Red? II. Solutions of Steady-State Stellar Structure
Po-Sheng Ou, Ke-Jung Chen
https://arxiv.org/abs/2506.07630 https://

Why Do Stars Turn Red? II. Solutions of Steady-State Stellar Structure
To investigate the physical origin of red giants (RGs) and red supergiants (RSGs), we construct steady-state models of stellar envelopes by explicitly solving the stellar structure equations, with boundary conditions set at the stellar surface and the hydrogen burning shell. For comparison, we consider both polytropic and realistic models. Polytropic models adopt a polytropic equation of state (EOS) and neglect energy transport, while realistic models incorporate radiative and convective energy…

Inhomogeneous stellar mixing in the final hours before the Cassiopeia A supernova
Toshiki Sato, Kai Matsunaga, Hiroyuki Uchida, Satoru Katsuda, Koh Takahashi, Hideyuki Umeda, Tomoya Takiwaki, Ryo Sawada, Takashi Yoshida, Ko Nakamura, Yui Kuboike, Paul P. Plucinsky, John P. Hughes
https://arxiv.org/abs/2507.07563

Inhomogeneous stellar mixing in the final hours before the Cassiopeia A supernova
Understanding stars and their evolution is a key goal of astronomical research and has long been a focus of human interest. In recent years, theorists have paid much attention to the final interior processes within massive stars, as they can be essential for revealing neutrino-driven supernova mechanisms and other potential transients of massive star collapse. However, it is challenging to observe directly the last hours of a massive star before explosion, since it is the supernova event that t…

A Theoretical Three-Dimensional Diagram to Separate Star Formation, Active Galactic Nuclei, and Shocks in Galaxies
Peixin Zhu, Lisa J. Kewley, Ralph S. Sutherland, Kathryn Grasha
https://arxiv.org/abs/2506.09962

A Theoretical Three-Dimensional Diagram to Separate Star Formation, Active Galactic Nuclei, and Shocks in Galaxies
The excitation sources in galaxies are frequently mixed due to AGN and stellar feedback, including star formation, active galactic nuclei (AGNs), and shock excitation. Disentangling the star formation, AGN, and shocks in galaxy integral-field spectra (IFU) at optical wavelengths is crucial to expanding the galaxy sample for AGN and stellar feedback studies, given the lack of multiwavelength observations for most of the galaxies that are observed in optical wavelengths. Previous methods to addre…

Computational thinking in the teaching of Stellar Astrophysics: Analysis 4 from a teaching intervention
Mart\'inez Raba Duv\'an Felipe, Moreno Cat\'olico Angie Alejandra, Valderrama Daniel Alejandro, Vargas Dom\'inguez Santiago
https://arxiv.org/abs/2507.03735

Computational thinking in the teaching of Stellar Astrophysics: Analysis 4 from a teaching intervention
This study designs, implements, and evaluates a teaching strategy based on computational thinking (CT) 27 to strengthen the teaching of stellar astrophysics in secondary education. Thirty-one 11th-grade students 28 from the Escuela Normal Superior Leonor Álvarez Pinzón (Tunja, Colombia) were worked with using an 29 action research approach. The methodology combined documentary analysis and practical application 30 through a teaching sequence of four workshops, integrating CT skills such as ab…

No influence of passing stars on paleoclimate reconstructions over the past 56 million years
Richard E. Zeebe, David M. Hernandez
https://arxiv.org/abs/2506.10158

No influence of passing stars on paleoclimate reconstructions over the past 56 million years
Passing stars (also called stellar flybys) have notable effects on the solar system's long-term dynamical evolution, injection of Oort cloud comets into the solar system, properties of trans-Neptunian objects, and more. Based on a simplified solar system model, omitting the Moon and the Sun's quadrupole moment J2, it has recently been suggested that passing stars are also an important driver of paleoclimate before ~50 Myr ago, including a climate event called the Paleocene-Eocene Thermal Maximu…

Str\"omgren photometric metallicity map of the Magellanic Cloud stars using Gaia DR3--XP spectra
Abinaya O. Omkumar, Maria-Rosa L. Cioni, Smitha Subramanian, Jos de Bruijne, Aparna Nair, Bruno Dias
https://arxiv.org/abs/2506.10749

Strömgren photometric metallicity map of the Magellanic Cloud stars using Gaia DR3--XP spectra
One important key in understanding a galaxy's evolution is to study the consequences of its past dynamical interactions that influenced its shape. By measuring the metallicity distribution of stellar populations with different ages, one can learn about these interactions. The Magellanic Clouds, being the nearest pair of interacting dwarf galaxies with a morphology characterised by different tidal and kinematic sub-structures as well as a vast range of stellar populations, represent an excellent…

Differentiable Stellar Atmospheres with Physics-Informed Neural Networks
Jiadong Li, Mingjie Jian, Yuan-Sen Ting, Gregory M. Green
https://arxiv.org/abs/2507.06357

Differentiable Stellar Atmospheres with Physics-Informed Neural Networks
We present Kurucz-a1, a physics-informed neural network (PINN) that emulates 1D stellar atmosphere models under Local Thermodynamic Equilibrium (LTE), addressing a critical bottleneck in differentiable stellar spectroscopy. By incorporating hydrostatic equilibrium as a physical constraint during training, Kurucz-a1 creates a differentiable atmospheric structure solver that maintains physical consistency while achieving computational efficiency. Kurucz-a1 can achieve superior hydrostatic equilib…

Supernovae from stellar mergers and accretors of binary mass transfer: Implications for Type IIP, 1987A-like and interacting supernovae
F. R. N. Schneider, E. Laplace, Ph. Podsiadlowski
https://arxiv.org/abs/2507.06391

Supernovae from stellar mergers and accretors of binary mass transfer: Implications for Type IIP, 1987A-like and interacting supernovae
As most massive stars are born in binary and other multiple-star systems, many are expected to exchange mass with a companion star or merge with it during their lives. This means that most supernovae (SNe) are from such binary products. Here, we focus on hydrogen-rich Type II SNe from accretors of binary mass transfer and stellar mergers. We compute various SN properties such as the explosion energies, nickel yields, and neutron star (NS) kick velocities, but also consider NS masses. We find ti…

TOI-1259Ab: A Warm Jupiter Orbiting a K-dwarf White-Dwarf Binary is on a Well-aligned Orbit
Hugo Veldhuis, Juan I. Espinoza-Retamal, Gudmundur Stefansson, Alexander P. Stephan, David V. Martin, David Bruijne, Suvrath Mahadevan, Joshua N. Winn, Cullen H. Blake, Fei Dai, Rachel B. Fernandes, Evan Fitzmaurice, Eric B. Ford, Mark R. Giovinazzi, Arvind F. Gupta, Samuel Halverson, Te Han, Daniel Krolikowski, Joe Ninan, Cristobal Petrovich, Paul Robertson, Arpita Roy, Christian Schwab, Ryan T…

TOI-1259Ab: A Warm Jupiter Orbiting a K-dwarf White-Dwarf Binary is on a Well-aligned Orbit
The evolution of one member of a stellar binary into a white dwarf has been proposed as a mechanism that triggers the formation of close-in gas giant planets. The star's asymmetric mass loss during the AGB stage gives it a "kick" that can initiate Eccentric Lidov-Kozai oscillations, potentially causing a planet around the secondary star to migrate inwards and perturbing the eccentricity and inclination of its orbit. Here we present a measurement of the stellar obliquity of TOI-1259Ab, a gas gia…

This https://arxiv.org/abs/2506.02763 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_…

Homogeneous Stellar Atmospheric Parameters and 22 Elemental Abundances for FGK Stars Derived From LAMOST Low-resolution Spectra with DD-Payne
A deep understanding of our Galaxy desires detailed decomposition of its stellar populations via their chemical fingerprints. This requires precise stellar abundances of many elements for a large number of stars. Here we present an updated catalog of stellar labels derived from LAMOST low-resolution spectra in a physics-sensible and rigorous manner with DD-Payne, taking labels from high-resolution spectroscopy as training set. The catalog contains atmospheric parameters for 6.4 million stars re…

Submillimeter and Mid-Infrared Variability of Young Stellar Objects in the M17 HII Region
Zhiwei Chen, Doug Johnstone, Carlos Contreras Pe\~na, Jeong-Eun Lee, Sheng-Yuan Liu, Gregory Herczeg, Steve Mairs, Geumsook Park, Kee-Tae Kim, Mi-Ryang Kim, Keping Qiu, Yao-Te Wang, Xu Zhang, Megan Reiter, the JCMT Transient Team
https://ar…

Submillimeter and Mid-Infrared Variability of Young Stellar Objects in the M17 HII Region
We conducted a comprehensive analysis of young stellar object (YSO) variability at submillimeter and mid-infrared (mid-IR) wavelengths for the M\,17 \ion{H}{2} region, using 3.5 years monitoring data from the JCMT Transient Survey at $450$ and $850\,μ$m and 9 years mid-IR monitoring data from the NEOWISE mission. Our study encompasses observations of 198 and 164 bright submillimeter peaks identified within the deep JCMT coadded maps at 450 and $850\,μ$m, and 66 YSOs seen by NEOWISE W2 that we…

X-ray emission of the Nuclear Stellar Disk as seen by SRG/ART-XC
Valentin Nezabudkin, Roman Krivonos, Sergey Sazonov, Rodion Burenin, Alexander Lutovinov, Ekaterina Filippova, Alexey Tkachenko, Mikhail Pavlinsky
https://arxiv.org/abs/2507.04319

X-ray emission of the Nuclear Stellar Disk as seen by SRG/ART-XC
The Nuclear Stellar Disk (NSD), together with the Nuclear Stellar Cluster and the supermassive black hole Sgr A*, forms the central region of the Milky Way. Galactic X-ray background emission is known to be associated with the old stellar population, predominantly produced by accreting white dwarfs. In this work we characterize the X-ray emission of the Galactic Center (GC) region using wide-field observations with the ART-XC telescope on board the SRG observatory in the 4-12 keV energy band. O…

Fundamental Parameters for Central Stars of 103 Infrared Bowshock Nebulae
Nikhil Patten, Henry A. Kobulnicky, Matthew S. Povich, Angelica S. Whisnant, Sydney Andrews, Alexandra Boone, Srujan Dandu, Naomi Jones, S. Nick Justice, Dylan Hope, Alexander Larsen, Ryan McCrory, Julia Meredith, Maria Renee Meza, Alexandra C. Rosenthal, William Salazar, Alexander R. Sterling, Noshin Yesmin, Daniel A. Dale

Fundamental Parameters for Central Stars of 103 Infrared Bowshock Nebulae
Stellar bowshock nebulae are arcuate shock fronts formed by the interaction of radiation-driven stellar winds and the relative motion of the ambient interstellar material. Stellar bowshock nebulae provide a promising means to measure wind-driven mass loss, independent of other established methods. In this work, we characterize the stellar sources at the center of bowshock nebulae drawn from all-sky catalogs of 24 $μ$m-selected nebulae. We obtain new, low-resolution blue optical spectra for \nu…

MINDS: Detection of an inner gas disk caused by evaporating bodies around HD 172555
M. Samland, T. Henning, A. Caratti o Garatti, T. Giannini, J. Bouwman, B. Tabone, A. M. Arabhavi, G. Olofsson, M. G\"udel, N. Pawellek, I. Kamp, L. B. F. M. Waters, D. Semenov, E. F. van Dishoeck, O. Absil, D. Barrado, A. Boccaletti, V. Christiaens, D. Gasman, S. L. Grant, H. Jang, T. Kaeufer, J. Kanwar, G. Perotti, K. Schwarz, M. Temmink

MINDS: Detection of an inner gas disk caused by evaporating bodies around HD 172555
Mechanisms such as collisions of rocky bodies or cometary activity give rise to dusty debris disks. Debris disks trace the leftover building blocks of planets, and thus also planetary composition. HD 172555, a stellar twin of beta Pic, hosts a debris disk thought to have resulted from a giant collision. It is known for its extreme mid-infrared silica dust feature, indicating a warm population of silica-rich grains in the asteroid belt (~5 au), cold CO observed by ALMA, and small bodies evaporat…

Dynamical mass distribution and velocity structure of the Galactic centre
A. Feldmeier-Krause, T. Ver\v{s}i\v{c}, G. van de Ven, E. Gallego-Cano, N. Neumayer
https://arxiv.org/abs/2506.06014

Dynamical mass distribution and velocity structure of the Galactic centre
The inner ~200 pc region of the Milky Way contains a nuclear stellar disc and a nuclear star cluster that are embedded in the larger Galactic bar. These stellar systems overlap spatially, which makes it challenging to separate stars that belong to the nuclear stellar systems, to deduce their internal dynamics, and to derive the central Galactic potential. Discrete stellar kinematics probe the mass distribution of a stellar system, and chemical tracers such as stellar metallicity can further sep…

Initial Characterization of Stellar Photometry of Roman images from the OpenUniverse Simulations
Lauren Aldoroty, Daniel Scolnic, Arun Kannawadi, Rob Knop, Benjamin Rose, Rebekah Hounsell, Michael Troxel
https://arxiv.org/abs/2506.04332

Initial Characterization of Stellar Photometry of Roman images from the OpenUniverse Simulations
NASA's Nancy Grace Roman Space Telescope (Roman) will provide an opportunity to study dark energy with unprecedented precision and accuracy using several techniques, including measurements of high-$z$ Type Ia Supernovae (SNe Ia, $z \lesssim 3.0$) via the High-Latitude Time Domain Survey (HLTDS). In this work, we do an initial "benchmark" characterization of the photometric repeatability of stellar fluxes, which must be below $1\%$ when sky noise is subdominant in order xto enable a number of ca…

Exoplanet Atmospheric Refraction Effects in the #Kepler Sample: https://arxiv.org/abs/2507.02126 -> "We present an analysis on the detection viability of refraction effects in Kepler's exoplanet atmospheres using binning techniques for their light curves in order to compare against simulated refraction effects. We split the Kepler exoplanets into sub-populations according to orbital period and planetary radius, then search for out-of-transit changes in the relative flux associated with atmospheric refraction of starlight. The presence of refraction effects - or lack thereof - may be used to measure and set limits on the bulk properties of an atmosphere, including mean molecular weight or the presence of hazes.
In this work, we use the presence of refraction effects to test whether exoplanets above the period-radius valley have H/He atmospheres, which high levels of stellar radiation could evaporate away, in turn leaving rocky cores below the valley. We find strong observational evidence of refraction effects for exoplanets above the period-radius valley based on Kepler photometry, however those related to optically thin H/He atmospheres are not common in the observed planetary population. This result may be attributed to signal dampening caused by clouds and hazes, consistent with the optically thick and intrinsically hotter atmospheres of Kepler exoplanets caused by relatively close host star proximity."

Magnetic Burial in Millisecond Magnetars and Late GRB Afterglow Signatures
Nissim Fraija, Cristian Giovanni Bernal, Antonio Galv\'an, Boris Betancourt-Kamenetskaia, Maria Giovanna Dainotti
https://arxiv.org/abs/2506.09402

Magnetic Burial in Millisecond Magnetars and Late GRB Afterglow Signatures
Millisecond magnetars, one of the potential candidates for the central engine of Gamma-ray bursts (GRBs), can experience significant magnetic field enhancement shortly after their formation. In some cases, this evolution is further influenced by the accretion of stellar debris, which modifies the dipole magnetic field strength. During a hypercritical accretion phase that lasts seconds or longer after the progenitor explosion, a thin crust may form, submerging the magnetic field (the so-called m…

The Internal Kinematics, Stellar Population, and Gas-phase Properties of The Pseudobulge in An Ultra-diffuse Galaxy: AGC721966
Shihong Liu, Yu Rong, Huiyuan Wang, Hong-Xin Zhang, Tie Li, Yao Yao, Zhicheng He, Teng Liu, Enci Wang, Cheng Cheng, Xu Kong
https://arxiv.org/abs/2506.07457

The Internal Kinematics, Stellar Population, and Gas-phase Properties of The Pseudobulge in An Ultra-diffuse Galaxy: AGC721966
Leveraging spectroscopic data from the Sloan Digital Sky Survey, we conduct a comprehensive analysis of the central stellar velocity dispersion, stellar population properties, star formation history, and gas-phase chemical abundances in AGC721966, a unique ultra-diffuse galaxy (UDG) harboring a pseudobulge. Our findings reveal that the pseudobulge formed in the early universe but underwent a recent episode of rejuvenated star formation. The system exhibits a mass-weighted (light-weighted) stell…

The ALMA Survey of Gas Evolution of PROtoplanetary Disks (AGE-PRO): VI. Comparison of Dust Evolution Models to AGE-PRO Observations
Nicolas T. Kurtovic, Matias G\'arate, Paola Pinilla, Ke Zhang, Giovanni P. Rosotti, Rossella Anania, Ilaria Pascucci, Beno\^it Tabone, Leon Trapman, Dingshan Deng, Miguel Vioque, John Carpenter, Lucas A. Cieza, Laura M. P\'erez, Carolina Agurto-Gangas, Anibal Sierra, Dary A. Ru\'iz-Rodriguez, James Miley, Camilo Gonz\'alez-Ruilova, Estephan…

The ALMA Survey of Gas Evolution of PROtoplanetary Disks (AGE-PRO): VI. Comparison of Dust Evolution Models to AGE-PRO Observations
The potential for planet formation of a circumstellar disk depends on the dust and gas reservoirs, which evolve as a function of the disk age. The ALMA Large Program AGE-PRO has measured several disk properties across three star-forming regions of different ages, and in this study we compare the observational results to dust evolution simulations. Using DustPy for the dust evolution, and RADMC-3D for the radiative transfer, we ran a large grid of models spanning stellar masses of 0.25, 0.50, 0.…

On the effect of the light bending phenomenon for a pulsar in a binary with a Kerr black hole
Jyotijwal Debnath, Manjari Bagchi
https://arxiv.org/abs/2506.05783

On the effect of the light bending phenomenon for a pulsar in a binary with a Kerr black hole
We study the effect of light-bending on the signal of a pulsar in binaries with rotating black hole companions, focusing on stellar mass black holes. We show that the impacts of various parameters on the bending delays visually match with those observed for a non-rotating black holes, because the magnitude of the spin as well as the orientation of the spin axis of the black hole introduce changes in the nanosecond order and other parameters do so in the microsecond order. Consequently, the dist…

[2025-06-13 Fri (UTC), 4 new articles found for astro-ph.SR Solar and Stellar Astrophysics]
toXiv_bot_toot

Spin-orbit misalignment and residual eccentricity are evidence that neutron star-black hole mergers form through triple star evolution
Jakob Stegmann, Jakub Klencki
https://arxiv.org/abs/2506.09121

Spin-orbit misalignment and residual eccentricity are evidence that neutron star-black hole mergers form through triple star evolution
There is growing evidence that a substantial fraction of the neutron star-black holes (NSBHs) detected through gravitational waves merge with non-zero eccentricity or large BH spin-orbit misalignment. This is in tension with the leading formation scenarios to date. Residual eccentricity rules out formation through isolated binary star evolution, while NS natal kicks and the unequal masses of NSBHs inhibit efficient pairing in dense stellar environments. Here, we report that all observed propert…

[2025-06-12 Thu (UTC), 11 new articles found for astro-ph.SR Solar and Stellar Astrophysics]
toXiv_bot_toot

Survey of Surveys. II. Stellar parameters for 23 millions of stars
A. Turchi, E. Pancino, A. Avdeeva, F. Rossi, M. Tsantaki, P. M. Marrese, S. Marinoni, N. Sanna, G. Fanari, D. Alvarez Garay, M. Echeveste, S. Nedhath, S. Rani, E. Reggiani, S. Saracino, L. Steinbauer, G. Thomas, F. Gran, G. Guiglion
https://arxiv.org/abs/2507.059…

Survey of Surveys. II. Stellar parameters for 23 millions of stars
In the current panorama of large surveys, the vast amount of data obtained with different methods, data types, formats, and stellar samples, is making an efficient use of the available information difficult. The Survey of Surveys is a project to critically compile survey results in a single catalogue, facilitating the scientific use of the available information. In this second release, we present two new catalogs of stellar parameters (Teff, logg, and [Fe/H]). To build the first catalog, SoS-Sp…

Open clusters in the outer disc studied with MEGARA@GTC Auner 1 and Berkeley 102
J. Carbajo-Hijarrubia, R. Carrera, F. Anders, C. Jordi, L. Casamiquela, L. Balaguer-N\'u\~nez, A. Gil de Paz
https://arxiv.org/abs/2506.10512

Open clusters in the outer disc studied with MEGARA@GTC Auner 1 and Berkeley 102
Open clusters offer crucial insights into stellar nucleosynthesis and the chemical evolution of the Galactic disc, as their ages and distances can be determined with higher accuracy compared to field stars. In this study, we investigate the outermost regions of the Milky Way disc using two previously unstudied open clusters -Auner 1 and Berkeley 102- located at Galactocentric distances of approximately 14 kpc in largely uncharted areas of the Galaxy. We obtained medium-resolution spectra (R > 1…

Coupling 1D stellar evolution with 3D-hydrodynamical simulations on-the-fly III: stellar evolution at different metallicities
Yixiao Zhou, Jakob L. R{\o}rsted, Achim Weiss, Andreas C. S. J{\o}rgensen, Cis Lagae, Luisa F. Rodr\'iguez D\'iaz, Yaguang Li, Mark L. Winther, Jens R. Larsen, J{\o}rgen Christensen-Dalsgaard, Oleg Kochukhov, Karen R. Pollard, Tanda Li

Coupling 1D stellar evolution with 3D-hydrodynamical simulations on-the-fly III: stellar evolution at different metallicities
A major weakness in one-dimensional (1D) stellar structure and evolution modeling is the simplified treatment of convection, which leads to erroneous near-surface stratification and considerable uncertainties in predicted effective temperatures and luminosities of low-mass stars. In a series of preceding works, a novel method for coupling 1D stellar structural models with a grid of 3D surface convection simulations during stellar evolution was developed, at solar metallicity. This 1D-3D couplin…

XRISM Spectroscopy of the Stellar-Mass Black Hole 4U 1630-472 in Outburst
Jon M. Miller (Univ. of Michigan), Misaki Mizumoto (Univ. of Teacher Education Fukuoka), Megumi Shidatsu (Ehime University), Ralf Ballhausen (Univ. of Maryland, College Park, NASA/GSFC, CRESST), Ehud Behar (Technion), Maria Diaz Trigo (ESO), Chris Done (Univ. of Durham), Tadayasu Dotani (ISAS), Javier Garcia (Caltech), Timothy Kallman (NASA/GSFC), Shogo B. Kobayashi (Tokyo Univ. of Science), Aya Kubota (Shibaura …

XRISM Spectroscopy of the Stellar-Mass Black Hole 4U 1630-472 in Outburst
We report on XRISM/Resolve spectroscopy of the recurrent transient and well-known black hole candidate 4U 1630$-$472 during its 2024 outburst. The source was captured at the end of a disk-dominated high/soft state, at an Eddington fraction of $λ_\mathrm{Edd} \sim 0.05~(10 M_{\odot}/M_\mathrm{BH})$. A variable absorption spectrum with unprecedented complexity is revealed with the Resolve calorimeter. This marks one of the lowest Eddington fractions at which highly ionized absorption has been de…

EP 250108a/SN 2025kg - observations of the most nearby Broad-Line Type Ic #Supernova following an Einstein Probe Fast X-ray Transient / The kangaroo's first hop - the early fast cooling phase of EP250108a/SN 2025kg: https://arxiv.org/abs/2504.08889 / https://arxiv.org/abs/2504.08886 -> Supernova’s ‘Trapped’ Jet Reveals Source of Fast X-ray Transient / International Gemini Observatory and SOAR Discover Surprising Link Between Fast X-ray Transients and the Explosive Death of Massive Stars: https://keckobservatory.org/fxt/ / https://noirlab.edu/public/news/noirlab2520/ - mysterious cosmic explosion is traced to a massive stellar explosion / a breakthrough in astronomy’s understanding of how stars larger than our Sun explode.

Synthesizing Sun-as-a-star flare spectra from high-resolution solar observations
M. De Wilde, A. G. M. Pietrow, M. K. Druett, A. Pastor Yabar, J. Koza, I. Kontogiannis, O. Andriienko, A. Berlicki, A. R. Brunvoll, J. de la Cruz Rodr\'iguez, J. T. Faber, R. Joshi, D. Kuridze, D. N\'obrega-Siverio, L. H. M. Rouppe van der Voort, J. Ryb\'ak, E. Scullion, A. M. Silva, Z. Vashalomidze, A. Vicente Ar\'evalo, A. Wi\'sniewska, R. Yadav, T. V. Zaqarashvili, J. Zbinden, E. S. …

Synthesizing Sun-as-a-star flare spectra from high-resolution solar observations
Spatially resolved observations of the Sun and the astronomical sample size of stellar bodies are the respective key strengths of solar and stellar observations. However, the large difference in object brightness between the Sun and other stars has led to distinctly different instrumentation and methodologies between the two fields. We produce and analyze synthetic full-disk spectra derived from 19 small area field-of-view optical observations of solar flares acquired by the Swedish 1-m Solar T…

The hot circumgalactic medium in stacked X-rays: observations vs simulations
Skylar Grayson, Evan Scannapieco, Johan Comparat, John A. ZuHone, Yi Zhang, Soumya Shreeram, Marcus Bruggen, Esra Bulbul
https://arxiv.org/abs/2506.09123

The hot circumgalactic medium in stacked X-rays: observations vs simulations
Current cosmological simulations rely on active galactic nuclei (AGN) feedback to quench star formation and match observed stellar mass distributions, but models for AGN feedback are poorly constrained. The circumgalactic medium (CGM) provides a helpful laboratory to study this process, as its metallicity, temperature, and density distributions are directly impacted by AGN. Recent observations from the eROSITA instrument provide constraints on these distributions through measurements of extende…

Entropy proxy inversions as tracers of the evolution of physical conditions at the base of the solar convective envelope
G. Buldgen, A. Noels, V. A. Baturin, J. Christensen-Dalsgaard, S. V. Ayukov, A. V. Oreshina, R. Scuflaire
https://arxiv.org/abs/2506.09503

Entropy proxy inversions as tracers of the evolution of physical conditions at the base of the solar convective envelope
The Sun is an important calibrator for the theory of stellar structure and evolution. However, the accuracy of our solar evolution models is tightly linked to the physical ingredients that enter their computations. This include, amongst other, the equation of state, the opacities, the transport of chemicals and the modelling of turbulent convection. Deriving model-independent probes of these ingredients is therefore crucial to further test the quality of these ingredients and potentially reveal…

Stellar Magnetic Storm Induced Magnetospheric Polarity Reversals: Distinguishing between Unmagnetised and Magnetised Exoplanets
Sakshi Gupta, Souvik Roy, Dibyendu Nandy
https://arxiv.org/abs/2506.02886

Stellar Magnetic Storm Induced Magnetospheric Polarity Reversals: Distinguishing between Unmagnetised and Magnetised Exoplanets
Exoplanetary and planetary environments are forced by stellar activity which manifest through variable radiation, particle and magnetic fluxes, stellar winds, flares and magnetic storms known as coronal mass ejections (CMEs). Recent studies have shown that (exo)planets with intrinsic magnetic fields and magnetospheres respond differently to this stellar forcing compared to planets which lack an intrinsic magnetism; this is borne out by observations in solar system planets. However, detailed inv…

Results from the Pan-STARRS Search for Kilonovae: Contamination by Massive Stellar Outbursts
M. D. Fulton, S. J. Smartt, M. E. Huber, K. W. Smith, K. C. Chambers, M. Nicholl, S. Srivastav, D. R. Young, E. A. Magnier, C. -C. Lin, P. Minguez, T. de Boer, T. Lowe, R. Wainscoat
https://arxiv.org/abs/2506.07082

Results from the Pan-STARRS Search for Kilonovae: Contamination by Massive Stellar Outbursts
We present results from the Pan-STARRS optical search for kilonovae without the aid of gravitational wave and gamma-ray burst triggers. The search was conducted from 26 October 2019 to 15 December 2022. During this time, we reported 29,740 transients observed by Pan-STARRS to the IAU Transient Name Server. Of these, 175 were Pan-STARRS credited discoveries that had a host galaxy within 200 Mpc and had discovery absolute magnitudes M > -16.5. A subset of 11 transients was plausibly identified as…

Deriving physical parameters of unresolved star clusters. IX. Sky background effects in the aperture photometry
Karolis Daugevi\v{c}ius, Rima Stonkut\.e, Eimantas Kri\v{s}\v{c}i\=unas, Erikas Cic\.enas, Vladas Vansevi\v{c}ius
https://arxiv.org/abs/2506.09622

Deriving physical parameters of unresolved star clusters. IX. Sky background effects in the aperture photometry
The aperture photometry method is a powerful tool that enables us to study large star cluster systems efficiently. However, its accuracy depends on various factors, including the stochasticity of the stellar initial mass function and variations in the sky background. Previously, in the eighth paper of this series, we established the best achievable limits of the aperture photometry method for star cluster studies in the local universe. The aim of this study is to determine how the sky backgroun…

Exploring the Eclipsing Binary System IY Aur: First Photometric Insights
N. Alan, M. Alpsoy, Y. Kilic
https://arxiv.org/abs/2506.09158 https://

Exploring the Eclipsing Binary System IY Aur: First Photometric Insights
Eclipsing binary systems play a vital role in astrophysics, as they provide a direct means of measuring fundamental stellar parameters. By combining high-precision space-based observations with ground-based multicolor photometric data, these parameters can be determined with greater accuracy. In this study, we present the first photometric analysis of the IY Aur eclipsing binary system, using a combination of the Transiting Exoplanet Survey Satellite (TESS) light curve and new UBVRI CCD observa…

Blue Stragglers prefer peaceful environments because binaries do the same
Francesco R. Ferraro, Barbara Lanzoni, Enrico Vesperini, Emanuele Dalessandro, Mario Cadelano, Cristina Pallanca, Giacomo Beccari, Domenico Nardiello, Mattia Libralato, Giampaolo Piotto
https://arxiv.org/abs/2506.07692…

Blue Stragglers prefer peaceful environments because binaries do the same
Blue straggler stars (BSSs) are core hydrogen-burning stars routinely observed in resolved stellar systems. According to the theory of single star evolution they should not exist because, due to their large mass, they should have already evolved to stellar remnants. Hence, they are suspected to be the result of mass-enhancement processes, like mass-transfer activity in binary systems, mergers in binary or higher order systems, or direct stellar collisions, possibly mediated by dynamical interac…

A Plasma Torus Around a Young Low-Mass Star
Luke G. Bouma, Moira M. Jardine
https://arxiv.org/abs/2506.09116 https://arxiv.org/pdf/25…

A Plasma Torus Around a Young Low-Mass Star
A small fraction of red dwarfs younger than 100 million years show structured, periodic optical light curves suggestive of transiting opaque material that corotates with the star. However, the composition, origin, and even the existence of this material are uncertain. The main alternative hypothesis is that these complex periodic variables (CPVs) are explained by complex distributions of bright or dark regions on the stellar surfaces. Here, we present time-series spectroscopy and photometry of …

X-Shooting ULLYSES: Massive stars at low metallicity. XIII. Putting the bi-stability jump to the test in the LMC
T. Alkousa (Astrophysics Research Cluster, School of Mathematical and Physical Sciences, University of Sheffield), P. A. Crowther (Astrophysics Research Cluster, School of Mathematical and Physical Sciences, University of Sheffield), J. M. Bestenlehner (Astrophysics Research Cluster, School of Mathematical and Physical Sciences, University of Sheffield, School of Chemical, M…

X-Shooting ULLYSES: Massive stars at low metallicity. XIII. Putting the bi-stability jump to the test in the LMC
We aim to investigate the theoretical bi-stability jump, which predicts an increase in mass-loss rates below 21 kK. We further aim to constrain the photospheric and wind parameters of a sample of 16 LMC late-O and B supergiants. We utilise the 1D, non-LTE radiative transfer model CMFGEN in a grid-based approach and subsequent fine-tuned spectroscopic fitting procedure to determine the stellar and wind parameters of each star. We apply this method to ultra-violet data from the ULLYSES programme …

A comprehensive study on radial velocity signals using ESPRESSO: Pushing precision to the 10 cm/s level
P. Figueira, J. P. Faria, A. M. Silva, A. Castro-Gonz\'alez, J. Gomes da Silva, S. G. Sousa, D. Bossini, M. R. Zapatero-Osorio, O. Balsalobre-Ruza, J. Lillo-Box, H. M. Tabernero, V. Adibekyan, R. Allart, S. Benatti, F. Bouchy, A. Cabral, S. Cristiani, X. Dumusque, J. I. Gonz\'alez-Hern\'andez, N. Hara, G. Lo Curto, C. Lovis, A. Mehner, P. Molaro, F. Pepe, N. C. Santos, D.…

A comprehensive study on radial velocity signals using ESPRESSO: Pushing precision to the 10 cm/s level
We analyse ESPRESSO data for the stars HD10700, HD20794, HD102365, and HD304636 acquired via its Guaranteed Time Observations (GTO) programme. We characterise the stars' radial velocity (RV) signals down to a precision of 10 cm/s on timescales ranging from minutes to planetary periods falling within the host's habitable zone (HZ). We study the RV signature of pulsation, granulation, and stellar activity, inferring the potential presence of planets around these stars. Thus, we outline the popula…

Pavo: Stellar feedback in action in a low-mass dwarf galaxy
Michael G. Jones, Martin P. Rey, David J. Sand, Kristine Spekkens, Burcin Mutlu-Pakdil, Elizabeth A. K. Adams, Paul Bennet, Denija Crnojevic, Amandine Doliva-Dolinsky, Richard Donnerstein, Catherine E. Fielder, Julia Healy, Laura C. Hunter, Ananthan Karunakaran, Deepthi S. Prabhu, Dennis Zaritsky

Pavo: Stellar feedback in action in a low-mass dwarf galaxy
MeerKAT observations of the recently discovered, extremely low mass galaxy, Pavo, have revealed a neutral gas (HI) reservoir that was undetected in archival HI single dish data. Based on the latest distance measurement ($2.16^{+0.08}_{-0.07}$ Mpc), we measure Pavo's HI mass as $\log M_\mathrm{HI}/\mathrm{M_\odot} = 5.79 \pm 0.05$, making it the lowest mass HI reservoir currently known in an isolated galaxy (with a robust distance measurement). Despite Pavo's extreme isolation, with no known nei…

Simulation of Binary-Single Interactions in AGN Disks II: Merger Probability of Binary Black Holes during Chaotic Triple Process
Mengye Wang, Qingwen Wu, Yiqiu Ma
https://arxiv.org/abs/2507.07715

Simulation of Binary-Single Interactions in AGN Disks II: Merger Probability of Binary Black Holes during Chaotic Triple Process
Stellar-mass binary black hole\,(BBH) mergers resulting from binary-single interactions\,(BSIs) in active galactic nucleus\,(AGN) disks are a potential source of gravitational wave\,(GW) events with measurable eccentricities. Previous hydrodynamical simulations have shown that ambient gas can significantly influence the dynamics of BSIs. However, due to limitations such as the use of purely Newtonian dynamics and small sample sizes, a direct estimation of the BBH merger probability during BSI h…

A core-sensitive mixed $f$/$g$ mode of the Sun predicted by wave topology and hydrodynamical simulation
Arthur Le Saux, Armand Leclerc, Guillaume Laibe, Pierre Delplace, Antoine Venaille
https://arxiv.org/abs/2506.09572

A core-sensitive mixed $f$/$g$ mode of the Sun predicted by wave topology and hydrodynamical simulation
Helioseismology has revolutionized our understanding of the Sun by analyzing its global oscillation modes. However, the solar core remains elusive, limiting a full understanding of its evolution. In this work, we study a previously unnoticed global oscillation mode of the Sun using a fully compressible, hydrodynamical simulation of the solar interior, and assess that it is a mixed $f$/$g$ mode with a period of about one hour. This is the first global stellar hydrodynamics simulation that succes…

Characterization of the Visual Binary TOI-6883AB and its dynamical implications for the planetary companion TOI-6883Ab
G. Conzo, F. Campos, F. Conti, I. Sharp
https://arxiv.org/abs/2506.08798

Characterization of the Visual Binary TOI-6883AB and its dynamical implications for the planetary companion TOI-6883Ab
We demonstrate that TOI-6883 is a physically bound visual binary system composed of two solar-type stars, TOI-6883A (TIC 393818343) and TOI-6883B (TIC 393818340), initially regarded as a single star hosting the exoplanet TOI-6883b. Gaia DR3 astrometry shows that both stars have nearly identical parallaxes 10.6 mas, consistent proper motions, and a projected separation of 616 AU, confirming their binary nature. Using astrometric and photometric data, we estimate the stellar masses, physical sepa…

Mass Distribution of Binary Black Hole Mergers from Young and Old Dense Star Clusters
Claire S. Ye (CITA), Maya Fishbach, Kyle Kremer, Marta Reina-Campos
https://arxiv.org/abs/2507.07183

Mass Distribution of Binary Black Hole Mergers from Young and Old Dense Star Clusters
Dense star clusters are thought to contribute significantly to the merger rates of stellar-mass binary black holes (BBHs) detected by the LIGO-Virgo-KAGRA collaboration. We combine $N$-body dynamic models of realistic dense star clusters with cluster formation histories to estimate the merger rate distribution as a function of primary mass for merging BBHs formed in these environments. It has been argued that dense star clusters -- most notably old globular clusters -- predominantly produce BBH…

This https://arxiv.org/abs/2505.07018 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_…

The competing effects of recent and long-term star formation histories on oxygen, nitrogen, and stellar metallicities
The fundamental metallicity relation (FMR) - the three-way trend between galaxy stellar masses, star-formation rates (SFRs) and gaseous metallicities - remains amongst the most studied extragalactic relations. Furthermore, metallicity correlates particularly tightly with gravitational potential. Simulations support a shared origin for these relations relating to long-term gas inflow history variations; however, differences between simulated and observed galaxy samples make it unclear whether th…

CLUES III: Do User Choices Impact The Results of SED Fitting? Tests of 'Off-The-Shelf' Stellar Population and Dust Extinction Models in the CLUES Sample
Andrew Mizener, Daniela Calzetti, Angela Adamo, Aida Wofford, Matthew J. Hayes, John Chisholm, Michele Fumagalli, Svea Hernandez, Matteo Maria Messa, Linda J. Smith, Arjan Bik, Kathryn Grasha, Mattia Sirressi

CLUES III: Do User Choices Impact The Results of SED Fitting? Tests of 'Off-The-Shelf' Stellar Population and Dust Extinction Models in the CLUES Sample
The simple stellar population models produced by stellar population and spectral synthesis (SPS) codes are used as spectral templates in a variety of astrophysical contexts. In this paper, we test the predictions of four commonly used stellar population synthesis codes (YGGDRASIL, BPASS, FSPS, and a modified form of GALAXEV which we call GALAXEVneb) by using them as spectral templates for photometric SED fitting with a sample of 18 young stellar clusters. All clusters have existing HST COS FUV …

SDSS-V Milky Way Mapper (MWM): ASPCAP Stellar Parameters and Abundances in SDSS-V Data Release 19
Szabolcs M\'esz\'aros, Paula Jofr\'e, Jennifer A. Johnson, Jonathan C. Bird, Andrew R. Casey, Katia Cunha, Nathan De Lee, Peter Frinchaboy, Guillaume Guiglion, Viola Heged\H{u}s, Alex P. Ji, Juna A. Kollmeier, Melissa K. Ness, Jonah Otto, Marc H. Pinsonneault, Alexandre Roman-Lopes, Amaya Sinha, Ying-Yi Song, Guy S. Stringfellow, Keivan G. Stassun, Jamie Tayar, Andrew Tkachenko…

SDSS-V Milky Way Mapper (MWM): ASPCAP Stellar Parameters and Abundances in SDSS-V Data Release 19
The goal of this paper is to describe the science verification of Milky Way Mapper (MWM) ASPCAP data products published in Data Release 19 (DR19) of the fifth phase of the Sloan Digital Sky Survey (SDSS-V). We compare MWM ASPCAP atmospheric parameters T$_{\rm eff}$, log g, 24 abundances of 21 elements (carbon, nitrogen, and oxygen have multiple sources for deriving their abundance values) and their uncertainties determined from APOGEE spectrograph spectra with those of the literature and evalua…

Giant planet formation via pebble accretion across different stellar masses
Sho Shibata, Ravit Helled
https://arxiv.org/abs/2507.01212 https://

Giant planet formation via pebble accretion across different stellar masses
The occurrence rate of cold Jupiters was found to depend on stellar mass. The formation environment in the protoplanetary disks regulates core formation and the subsequent gas accretion. In this study, we simulate giant planet formation via pebble accretion accounting for various stellar masses, core formation times, disk turbulent viscosities, and grain opacities. We use a self-consistent formation model that calculates the solid accretion rate and gas accretion rate of growing protoplanets. W…

The Impact of Natal Kicks on Black Hole Binaries
Alejandro Vigna-G\'omez
https://arxiv.org/abs/2507.07573 https://arxiv.org/pdf/2…

The Impact of Natal Kicks on Black Hole Binaries
In massive binary-star systems, supernova explosions can significantly alter the orbit during the formation of compact objects. Some compact objects are predicted to form via direct collapse, a scenario with negligible mass loss and no baryonic ejecta emitted. In this scenario, most of the energy is released via neutrinos, and any resulting natal kick arises from asymmetries in their emission. Here I investigate stellar collapse leading to binary black hole (BH) formation, with a focus on how t…

Stellar distributions around supermassive black holes in gas-rich nuclear star clusters
Mor Rozner, Enrico Ramirez-Ruiz
https://arxiv.org/abs/2506.04229 ht…

Stellar distributions around supermassive black holes in gas-rich nuclear star clusters
We study the stellar distribution around supermassive black holes (SMBHs) in gas-rich nuclear star clusters (NSCs). NSCs could contain vast amounts of gas, which contribute significantly to shaping the stellar distribution, typically altering the stellar density cusp from the usual Bahcall \& Wolf 1976 solution and consequently affecting the dynamics in the NSC. The dense gaseous environment in NSCs gives rise to dynamical phenomena that are otherwise rare in other gas-free environments. Here w…

Replaced article(s) found for astro-ph.SR. https://arxiv.org/list/astro-ph.SR/new
[1/1]:
- Fragmentation of Dense Rotation-Dominated Structures Fed by Collapsing Gravomagneto-Sheetlets and...
Yisheng Tu, Zhi-Yun Li, Zhaohuan Zhu, Chun-Yen Hsu

A high stellar multiplicity rate amongst TESS planet candidates in the Neptunian desert using Gaia DR3 astrometry
Fintan Eeles-Nolle, David J. Armstrong
https://arxiv.org/abs/2506.22399

A high stellar multiplicity rate amongst TESS planet candidates in the Neptunian desert using Gaia DR3 astrometry
We aim to discover whether the stellar multiplicity rate may provide information on the origin of recently discovered planets in the Neptunian Desert. Using Gaia DR3 astrometry, we search for common proper motion companions to 1779 known exoplanet hosts and 2927 exoplanet candidate hosts from the TESS mission, both within 650 pc. We find overall stellar multiplicity rates of $16.6\pm0.9\%$ and $19.8\pm0.6\%$ for confirmed and candidate exoplanets, respectively. We find stellar multiplicity rate…

Constraining the Milky Way Halo Accretion History With Simulated Stellar Halos: Designing the HALO7D-X Survey
Miranda Apfel, Kevin A. McKinnon, Constance M. Rockosi, Puragra Guhathakurta, Kathryn V. Johnston
https://arxiv.org/abs/2507.05239

Constraining the Milky Way Halo Accretion History With Simulated Stellar Halos: Designing the HALO7D-X Survey
We present the design for HALO7D-X, a survey of the stellar halo to investigate the accretion history of the Milky Way. The survey will use a combination of Hubble Space Telescope (HST) and Gaia data for sky position and proper motions of faint stars (18

Giants, Supergiants and Hypergiants
Lee R. Patrick
https://arxiv.org/abs/2507.06970 https://arxiv.org/pdf/2507.06970

Giants, Supergiants and Hypergiants
Observing the stars in our night sky tells us that giant, supergiant and hypergiant stars hold an unique importance in the understanding of stellar populations. Theoretical stellar models predict a rich tapestry of evolved stars. These evolved stars result in supernova explosions for massive stars and the shedding of the outer layers of low- and intermediate-mass stars to form white dwarf stars. Stars on these pathways provide elemental and kinematic feedback that shapes their host galaxies and…

Statistical nuclear spin ratios of deuterated ammonia in the pre-stellar core L1544
Jorma Harju (Max-Planck-Institut fuer extraterrestrische Physik, Department of Physics, University of Helsinki), Paola Caselli (Max-Planck-Institut fuer extraterrestrische Physik), Olli Sipilae (Max-Planck-Institut fuer extraterrestrische Physik), Silvia Spezzano (Max-Planck-Institut fuer extraterrestrische Physik), Arnaud Belloche (Max-Planck-Institut fuer Radioastronomie), Luca Bizzocchi (Dipartimento…

Statistical nuclear spin ratios of deuterated ammonia in the pre-stellar core L1544
We determined the ortho/para (o/p) ratios of NH2D and NHD2 in the archetypical pre-stellar core L1544. The core was observed in the two lowest rotational lines of ortho- and para-NH2D using the APEX and the IRAM 30 m telescopes. The ground-state lines of ortho- and para-NHD2 were observed with APEX. The distributions of chemical abundances in the core were predicted using a gas-grain chemistry model with two different scenarios concerning proton transfer reactions in the gas. One of the scenari…

Resolving the Unresolved: Using NESSI to Search for Unresolved Companions in Low-mass Disk Wide Binaries
Zachary D. Hartman, Gerard van Belle, S\'ebastien L\'epine, Mark E. Everett, Ilija Medan
https://arxiv.org/abs/2506.07499

Resolving the Unresolved: Using NESSI to Search for Unresolved Companions in Low-mass Disk Wide Binaries
Stellar systems consisting of three or more stars are not an uncommon occurrence in the Galaxy. Nearly 50% of solar-type wide binaries with separations >1000 au are actually higher-order multiples with one component being a close binary. Additionally, the higher-order multiplicity fraction appears to be correlated with the physical separation of the widest component. These facts have motivated some of our current theories behind how the widest stellar systems formed, which can have separations …

The EDGE-CALIFA Survey: An integral field unit-based integrated molecular gas database for galaxy evolution studies in the Local Universe
D. Colombo, V. Kalinova, Z. Bazzi, S. F. Sanchez, A. D. Bolatto, T. Wong, V. Villanueva, N. Mudivarthi, E. Rosolowsky, A. Wei{\ss}, K. D. French, A. Leroy, J. Barrera-Ballesteros, Y. Garay-Solis, F. Bigiel, A. Tripathi, B. Rodriguez

The EDGE-CALIFA Survey: An integral field unit-based integrated molecular gas database for galaxy evolution studies in the Local Universe
Studying galaxy evolution requires knowledge not only of the stellar properties, but also of the interstellar medium (in particular the molecular phase) out of which stars form, using a statistically significant and unbiased sample of galaxies. To this end, we introduce here the integrated Extragalactic Database for Galaxy Evolution (iEDGE), a collection of integrated stellar and nebular emission lines, and molecular gas properties from 643 galaxies in the local Universe. These galaxies are dra…

Turbulent drag on stellar mass black holes embedded in AGN discs
Alessandro Alberto Trani, Pierfrancesco Di Cintio
https://arxiv.org/abs/2506.02173 https:/…

Turbulent drag on stellar mass black holes embedded in AGN discs
We investigate how AGN disk turbulence affects the orbital dynamics of a stellar-mass black hole (BH) initially located at a migration trap, focusing on the long-term behavior of eccentricity and inclination in the quasi-embedded regime. We develop a semi-analytical framework in which turbulence is modeled as a stochastic velocity field acting through a modified drag force. We integrate the resulting stochastic differential equations both in Cartesian coordinates and in orbital elements using a…

Going Bayesian on the ages of nearby young stellar systems I. The expansion rate method
J. Olivares, A. Berihuete, H. Bouy
https://arxiv.org/abs/2506.05110

Going Bayesian on the ages of nearby young stellar systems I. The expansion rate method
Context. Determining the ages of young stellar systems is fundamental to test and validate current star-formation theories. Aims. We aim at developing a Bayesian version of the expansion rate method that incorporates the a priori knowledge on the stellar system's age and solves some of the caveats of the traditional frequentist approach. Methods. We upgrade an existing Bayesian hierarchical model with additional parameter hierarchies that include, amongst others, the system's age. For this late…

A giant planet transiting a 0.2 solar mass host star
Edward M. Bryant, Andr\'es Jord\'an, Joel D. Hartman, Daniel Bayliss, Elyar Sedaghati, Khalid Barkaoui, Jamila Chouqar, Francisco J. Pozuelos, Daniel P. Thorngren, Mathilde Timmermans, Jose Manuel Almenara, Igor V. Chilingarian, Karen A. Collins, Tianjun Gan, Steve B. Howell, Norio Narita, Enric Palle, Benjamin V. Rackham, Amaury H. M. J. Triaud, Gaspar \'A. Bakos, Rafael Brahm, Melissa J. Hobson, Vincent Van Eylen, Pedro…

A giant planet transiting a 0.2 solar mass host star
Planet formation models suggest that the formation of giant planets is significantly harder around low-mass stars, due to the scaling of protoplanetary disc masses with stellar mass. The discovery of giant planets orbiting such low-mass stars thus imposes strong constraints on giant planet formation processes. Here, we report the discovery of a transiting giant planet orbiting a $0.207 \pm 0.011 M_{\odot}$ star. The planet, TOI-6894 b, has a mass and radius of $M_P = 0.168 \pm 0.022 M_J (53.4 \…

Homogeneous Stellar Atmospheric Parameters and 22 Elemental Abundances for FGK Stars Derived From LAMOST Low-resolution Spectra with DD-Payne
Meng Zhang, Maosheng Xiang, Yuan-Sen Ting, Anish Maynur Amarsi, Hua-Wei Zhang, Jianrong Shi, Haibo Yuan, Haining Li, Jiahui Wang, Yaqian Wu, Tianmin Wu, Lanya Mou, Hong-liang Yan, Jifeng Liu
https://

Homogeneous Stellar Atmospheric Parameters and 22 Elemental Abundances for FGK Stars Derived From LAMOST Low-resolution Spectra with DD-Payne
A deep understanding of our Galaxy desires detailed decomposition of its stellar populations via their chemical fingerprints. This requires precise stellar abundances of many elements for a large number of stars. Here we present an updated catalog of stellar labels derived from LAMOST low-resolution spectra in a physics-sensible and rigorous manner with DD-Payne, taking labels from high-resolution spectroscopy as training set. The catalog contains atmospheric parameters for 6.4 million stars re…

Hydrostatic and explosive $\alpha$-element chemical abundances of Milky Way globular clusters, halo substructures, and satellite galaxies
Danny Horta, Melissa K. Ness
https://arxiv.org/abs/2506.08079

Hydrostatic and explosive $α$-element chemical abundances of Milky Way globular clusters, halo substructures, and satellite galaxies
Stellar atmospheric element abundance ratios of stars retain information about their birth conditions, helping elucidate their origin and nature. In this letter, we analyse and contrast the hydrostatic and explosive $α$-element abundance ratios, and the ratio of the two (the hex ratio), for a large sample of Galactic globular clusters (GCs), halo substructures, satellite galaxies, and the Milky Way high-/low-$α$ discs using data from the $APOGEE$ survey. Our results show that: $i$) Milky Way …

Search for High Energy Neutrinos from Infrared Flares
Teresa Pernice (for the IceCube Collaboration), Giacomo Sommani (for the IceCube Collaboration)
https://arxiv.org/abs/2507.06934

Search for High Energy Neutrinos from Infrared Flares
IceCube has detected a diffuse flux of high-energy neutrinos, whose origin still remains uncertain. Accreting supermassive black holes (SMBHs) have been proposed as plausible sources of neutrinos. Candidate sources include AT2019dsg, which is likely a stellar tidal disruption event (TDE), and AT2019dfr, an AGN flare. Both present delayed emission in the IR band with respect to the optical signal. This emission can be interpreted as the reprocessing of X-rays to optical light of the flare by dus…

[2025-07-11 Fri (UTC), 7 new articles found for astro-ph.SR Solar and Stellar Astrophysics]
toXiv_bot_toot

[2025-06-11 Wed (UTC), 13 new articles found for astro-ph.SR Solar and Stellar Astrophysics]
toXiv_bot_toot

Exploring over 700 massive quiescent galaxies at z = 2-7: Demographics and stellar mass functions
William M. Baker, Francesco Valentino, Claudia del P. Lagos, Kei Ito, Christian Kragh Jespersen, Rashmi Gottumukkala, Jens Hjorth, Danial Langeroodi, Aidan Sedgewick
https://arxiv.org/abs/2506.04119

Exploring over 700 massive quiescent galaxies at z = 2-7: Demographics and stellar mass functions
High-redshift ($z>2$) massive quiescent galaxies are crucial tests of early galaxy formation and evolutionary mechanisms through their cosmic number densities and stellar mass functions (SMFs). We explore a sample of 745 massive ($\rm M_*> 10^{9.5}M_\odot$) quiescent galaxies from $z=2-7$ in over 800 arcmin$^2$ of NIRCam imaging from a compilation of public JWST fields (with a total area $>$ 5 $\times$ previous JWST studies). We compute and report their cosmic number densities, stellar mass fun…

Probing Binary Architectures of Lithium-Rich Giants in GALAH with COSMIC and Stellar Models
Maryum Sayeed, Selina Yang, Giulia Cinquegrana, Melissa K. Ness, Katelyn Breivik, Andrew R. Casey, Sven Buder, Amanda I. Karakas
https://arxiv.org/abs/2507.05359

Probing Binary Architectures of Lithium-Rich Giants in GALAH with COSMIC and Stellar Models
Surface lithium is depleted when a star goes through the first dredge-up phase, yet $1\%$ of red giants are found to be Li-rich. The formation mechanism for these remains uncertain. We combine observational constraints from GALAH Li-rich giants, with the binary population synthesis code COSMIC to investigate system properties of these objects assuming binary mass transfer. By evolving 9 million binary systems, we find that binary histories most consistent with observational constraints are mass…

The central spectra of massive star-forming galaxies
Jaimie R. Sheil, Michael J. I . Brown, Virginia A. Kilborn, Michelle E. Cluver, Thomas Jarrett
https://arxiv.org/abs/2506.08474

The central spectra of massive star-forming galaxies
We have examined the nuclear spectra of very massive star-forming galaxies at $z \sim 0$ to understand how they differ from other galaxies with comparable masses, which are typically passive. We selected a sample of 126 nearby massive star-forming galaxies ($<100~{\rm Mpc}$, $10^{11.3}~\rm{M_\odot} \leq M_{\rm stellar} \leq 10^{11.7}~\rm{M_\odot}$, $1 ~{\rm M_\odot~yr^{-1}}< {\rm SFR} <13 ~{\rm M_\odot~yr^{-1}}$) from the 2MRS-Bright WXSC catalogue. LEDA morphologies indicate at least 63\% of o…

Dynamical mass of the Serpens intermediate-mass young stellar system EC\,95 with DYNAMO--VLBA
Jazm\'in Ord\'o\~nez-Toro (Instituto de Radioastronom\'ia y Astrof\'isica, Universidad Nacional Aut\'onoma de M\'exico, M\'exico), Sergio A. Dzib (Max Planck Institut f\"ur Radioastronomie, Germany), Laurent Loinard (Instituto de Radioastronom\'ia y Astrof\'isica, Universidad Nacional Aut\'onoma de M\'exico, M\'exico, Black Hole Initiative a…

Dynamical mass of the Serpens intermediate-mass young stellar system EC\,95 with DYNAMO--VLBA
We present dynamical mass measurements, obtained from multi-epoch Very Long Baseline Interferometry (VLBI) observations, for the young multiple stellar system EC\,95, located in the core of the Serpens star-forming region. Our dataset includes both archival data and more recent observations obtained as part of the \textit{Dynamical Masses of Young Stellar Multiple Systems with the VLBA project} (DYNAMO--VLBA), totalling 32 epochs over 12 years of observation. The observations span more than hal…

The properties of primordially-seeded black holes and their hosts in the first billion years: implications for JWST
Pratika Dayal, Roberto maiolino
https://arxiv.org/abs/2506.08116

The properties of primordially-seeded black holes and their hosts in the first billion years: implications for JWST
James Webb Space Telescope (JWST) observations have opened a tantalising new window onto possible black holes as early as redshifts of $z \sim 10.4$. These show a number of puzzling properties including unexpectedly massive black holes in place by $z \sim 10$ and inexplicably high black hole-to-stellar mass ratios of $M_{\rm BH}/M_*\geq 0.1$. These pose a serious challenge for "astrophysical" seeding and growth models that we aim to explain with ``cosmological" primordial black holes (PBHs) in …

Probing neutral outflows in z ~ 2 galaxies using JWST observations of Ca II H and K absorption lines
Caterina Liboni, Sirio Belli, Letizia Bugiani, Rebecca Davies, Minjung Park, Charlie Conroy, Razieh Emami, Benjamin D. Johnson, Amir H. Khoram, Joel Leja, Gabriel Maheson, Matteo Sapori, Trevor Mendel, Sandro Tacchella, Rainer Weinberger
https://

Probing neutral outflows in z ~ 2 galaxies using JWST observations of Ca II H and K absorption lines
Using deep JWST/NIRSpec spectra from the Blue Jay survey, we perform the first systematic investigation of neutral gas content in massive galaxies at Cosmic Noon based on the Ca II H, K absorption lines. We analyze a sample of 9 galaxies at 1.8 < z < 2.8 with stellar masses > 10.6, for which we detect neutral gas absorption both in Ca II and in Na I. After removing the stellar continuum using the best-fit model obtained with Prospector, we fit the excess absorption due to neutral gas in the Ca …

Bayesian ages of local young stellar associations I. Through the expansion rate method
J. Olivares, N. Miret-Roig, P. A. B. Galli, H. Bouy
https://arxiv.org/abs/2506.05130

Bayesian ages of local young stellar associations I. Through the expansion rate method
Context. Local young stellar associations (LYSAs <50 Myr and <150 pc) are important laboratories to test predictions from star-formation theories. Estimating their ages through various dating techniques with minimal biases is thus of paramount importance. Aims. We aim at determining the ages of LYSAs with the expansion rate dating technique. Methods. We estimate the ages of the LYSAs using literature membership lists, publicly available data (astrometry and radial velocities), and a recent open…

UVIT Study of the Magellanic Clouds (U-SMAC). III. Hierarchical Star Formation in the Small Magellanic Cloud Regulated by Turbulence
Sipra Hota, Richard de Grijs, Annapurni Subramaniam
https://arxiv.org/abs/2506.08951

UVIT Study of the Magellanic Clouds (U-SMAC). III. Hierarchical Star Formation in the Small Magellanic Cloud Regulated by Turbulence
The Small Magellanic Cloud (SMC), a satellite galaxy of the Milky Way, is an irregular dwarf galaxy exhibiting evidence of recent and ongoing star formation. We performed a spatial clustering analysis of far-ultraviolet stars in the SMC younger than 150 Myr using data from the Ultra Violet Imaging Telescope onboard AstroSat. We identified 236 young stellar structures as surface overdensities at different significance levels. The sizes of these structures range from a few parsecs to several hund…

Replaced article(s) found for astro-ph.SR. https://arxiv.org/list/astro-ph.SR/new
[1/1]:
- Flaring Stars in a Non-targeted mm-wave Survey with SPT-3G
C. Tandoi, et al.

Anchoring Stellar Age Indicators: A Cross-Calibration of [C/N] and Gyrochronology Ages via the Age-Velocity-Dispersion Relation
Yuxi Lu, Marc H. Pinsonneault, Yuan-Sen Ting, Phil R. Van-Lane, John D Roberts, Jamie Tayar, Alexander Stone-Martinez
https://arxiv.org/abs/2506.24010

Anchoring Stellar Age Indicators: A Cross-Calibration of [C/N] and Gyrochronology Ages via the Age-Velocity-Dispersion Relation
Determining stellar ages is challenging, as it depends on other stellar parameters in a non-linear way and often relies on stellar evolution models to infer the underlying relation between these parameters and age. This complexity increases when comparing different age-dating methods, as they rely on distinct indicators and are often applicable to non-overlapping regions of the color-magnitude diagram. Moreover, many empirical calibration methods rely on pre-determined ages, often from open clu…

Stellar-gas kinematic misalignments in EAGLE: enhanced SMBH growth in misaligned galaxies
Maximilian K. Baker, Timothy A. Davis, Freeke van de Voort, Sandra I. Raimundo
https://arxiv.org/abs/2507.01894

Stellar-gas kinematic misalignments in EAGLE: enhanced SMBH growth in misaligned galaxies
Stellar-gas kinematic misalignments are a transient phenomenon observed in $\sim11\%$ of the local galaxy population. According to current models, misaligned gas is expected to lose angular momentum and relax into the galactic plane on timescales of $\sim0.1$ Gyr, driving gas toward the central regions of the galaxy. Recent observational studies have found a higher incidence of active galactic nuclei in misaligned galaxies. We use the EAGLE simulation to explore the connection between stellar-g…

Stellar Mass Segregation in Dark Matter Halos
Rapha\"el Errani, Jorge Pe\~narrubia, Matthew G. Walker
https://arxiv.org/abs/2505.22717 https://…

Stellar Mass Segregation in Dark Matter Halos
We study the effect of stellar mass segregation driven by collisional relaxation within the potential well of a smooth dark matter halo. This effect is of particular relevance for old stellar systems with short crossing times, where small collisional perturbations accumulate over many dynamical time scales. We run collisional $N$-body simulations tailored to the ambiguous stellar systems Ursa Major 3/Unions 1, Delve 1 and Eridanus 3, modelling their stellar populations as two-component systems …

Stellar populations in STARFORGE II: Comparison with observations
Juan P. Farias, Stella S. R. Offner, Ronan Kerr, Michael Y. Grudi\'c
https://arxiv.org/abs/2506.00240

Stellar populations in STARFORGE II: Comparison with observations
Recent studies suggest that most star-forming regions in our Galaxy form stellar associations rather than bound clusters. We analyse models from the STARFORGE simulation suite, a set of magneto-hydrodynamical simulations that include all key stellar feedback and radiative processes following star formation through cloud dispersal. We create synthetic observations by introducing observational biases such as random spurious measurements, unresolved binaries, and photometric sensitivity. These bia…

This https://arxiv.org/abs/2412.03662 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_…

The Growth of Galaxy Stellar Haloes Over $0.2 \leq z \leq 1.1$
Galaxies are predicted to assemble their stellar haloes through the accretion of stellar material from interactions with their cosmic environment. Observations that trace stellar halo buildup probe the processes that drive galaxy size and stellar mass growth. We investigate stellar halo assembly over $0.2 \leq z \leq 1.1$ in a mass-complete ($M_{\star} \geq 10^{9.5}M_{\odot}$) sample of 242,456 star-forming and 88,421 quiescent galaxies (SFGs and QGs) from the CLAUDS and HSC-SSP surveys. We ext…

This https://arxiv.org/abs/2506.04119 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_…

Exploring over 700 massive quiescent galaxies at z = 2-7: Demographics and stellar mass functions
High-redshift ($z>2$) massive quiescent galaxies are crucial tests of early galaxy formation and evolutionary mechanisms through their cosmic number densities and stellar mass functions (SMFs). We explore a sample of 745 massive ($\rm M_*> 10^{9.5}M_\odot$) quiescent galaxies from $z=2-7$ in over 800 arcmin$^2$ of NIRCam imaging from a compilation of public JWST fields (with a total area $>$ 5 $\times$ previous JWST studies). We compute and report their cosmic number densities, stellar mass fun…

[2025-07-10 Thu (UTC), 6 new articles found for astro-ph.SR Solar and Stellar Astrophysics]
toXiv_bot_toot

[2025-06-10 Tue (UTC), 18 new articles found for astro-ph.SR Solar and Stellar Astrophysics]
toXiv_bot_toot

Rapid stellar and binary population synthesis with COMPAS: methods paper II
Ilya Mandel, Jeff Riley, Adam Boesky, Adam Brcek, Ryosuke Hirai, Veome Kapil, Mike Y. M. Lau, JD Merritt, Nicol\'as Rodr\'iguez-Segovia, Isobel Romero-Shaw, Yuzhe Song, Simon Stevenson, Avi Vajpeyi, L. A. C. van Son, Alejandro Vigna-G\'omez, Reinhold Willcox
https…

Rapid stellar and binary population synthesis with COMPAS: methods paper II
The COMPAS public rapid binary population synthesis code has undergone a number of key improvements since the original COMPAS methods paper (Team COMPAS: Riley et al., 2022) was published. These include more sophisticated and robust treatments of binary interactions: mass transfer physics, common-envelope events, tides and gravitational-wave radiation reaction; and updated prescriptions for stellar evolution, winds and supernovae. The code structure and outputs have also been updated, with a fo…

Replaced article(s) found for astro-ph.SR. https://arxiv.org/list/astro-ph.SR/new
[1/1]:
- Brown dwarf number density in the JWST COSMOS-Web field
Chen, Goto, Wu, Ling, Kim, Ho, Kilerci, Uno, Phan, Lin, Yang, Hashimoto

The stellar population in the SARAO MeerKAT Galactic Plane Survey
Okwudili D. Egbo, David A. H. Buckley, Paul J. Groot, Francesco Cavallaro, Patrick A. Woudt, Mark A. Thompson, Mubela Mutale, Michael Bietenholz
https://arxiv.org/abs/2505.22139

The stellar population in the SARAO MeerKAT Galactic Plane Survey
We report on optically selected stellar candidates of SARAO MeerKAT 1.3 GHz radio continuum survey sources of the Galactic plane. Stellar counterparts to radio sources are selected by cross-matching the MeerKAT source positions with \textit{Gaia} DR3, using two approaches. The first approach evaluated the probability of chance alignments between the radio survey and \textit{Gaia} sources and used AllWISE infrared colour-colour information to select potential stellar candidates. The second appro…

Limb-Darkening Coefficients for the 4-Term and Power-2 Laws for the JWST Space Mission, Adopting PHOENIX Spherical Models at High Resolution
A. Claret (IAA), P. H. Hauschildt (Hamburger Sternwarte), G. Torres (CfA)
https://arxiv.org/abs/2506.07265

Limb-Darkening Coefficients for the 4-Term and Power-2 Laws for the JWST Space Mission, Adopting PHOENIX Spherical Models at High Resolution
Modeling observations of transiting exoplanets or close binary systems by comparing the observations with theoretical light curves requires precise knowledge of the distribution of specific intensities across the stellar disk. We aim to facilitate this type of research by providing extensive tabulations of limb-darkening coefficients for 11 frequently used near- and mid-infrared passbands on the NIRCam, NIRISS, and NIRSpec instruments installed on board the James Webb Space Telescope. The calcu…

Fifty Years of CAK
Jorick S. Vink (Armagh Observatory,Planetarium)
https://arxiv.org/abs/2506.06421 https://arxiv.org/pdf/2506.06421

Fifty Years of CAK
We present a new framework for massive star evolution that is no longer driven by Dutch or other mass-loss rate Recipes, but which take the physics of Gamma or L/M dependent mass loss consistently into account. We first discuss the hot-star mass-loss kink and the transition mass loss rate between optically thin and thick winds, before discussing vertical stellar evolution, mass evaporation, and the maximum black hole (BH) mass. We end with a suggestion that a recently uncovered red supergiant (…

The effect of local magnetic fields in quiet regions of stellar atmospheres simulated with MANCHA
Andrea Perdomo Garc\'ia, Nikola Vitas, Elena Khomenko, Manuel Collados
https://arxiv.org/abs/2507.00636

The effect of local magnetic fields in quiet regions of stellar atmospheres simulated with MANCHA
Our aim is to characterize the effects of the local magnetic fields in quiet regions of stellar atmospheres. We compute magneto-hydrodynamic and purely hydrodynamic simulations of G2V, K0V and M2V star. The magnetic simulations are started from the hydrodynamical ones, adding the Biermann battery term in the induction equation to produce a magnetic seed, that is enhanced by the action of the small-scale dynamo. Once the magnetic field is saturated, we compare the simulations with and without ma…